Relay.



PATENTED DEC; 11, 1906.

. R. HANNA.

RELAY.

APPLICATION FILED MAY 26.1906.

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Invenifor:

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No. 838,404. PATBNTED DEC. 11, 1906. M, R. HANNA.

RELAY; APPLICATION FILED MAY 26. 1906,

2 SHEETS-SHEET 2.

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' Max R Hanna. y M M783.

UNITE STATES PATENT OFFICE.

MAX R. HANNA, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, CORPORATION OF NEW YORK.

RELAY.

Specification of Letters Patent.

Patented Dec. 11, 1906.

Application filed May 26,1906- Serial No. 318,879.

T0 at ZOh/OWZ/ it may concern:

Be it known that 1, MAX R. HANNA, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Relays, of which the following is a specification.

My invention relates to relays for block signal systems for electrically-operated roads, in which the rails are employed as returnconductor for the power-current; and its obj ect is to provide a novel construction of relay which can exert a high torque with a small expenditure of energy in the track-circuits.

It has been proposed heretofore on directcurrent roads to employ alternating current for the signal system and to use relays which will not be -aii'ected by the power-current. One suitable form of relay for this purpose is the induction type having one phase supplied from the track-circuit and another phase supplied from an independent source of current with a short-circuited conducting member in inductive relation to thetwo phases. On account of the high impedance I offered by the track-rails and also on account of the design of the track transformer or transformers, which must ordinarily be arranged with very poor regulation in order to avoid saturation by the power-current, the transmission-circuit which supplies current to one phase of the relay-coil is of very low efiiciency, while the circuit of the other phase which simply connects that phase directly to the source, may be of very high efficiency. Consequently it is desirable that the greater part of the energy supplied to the relay should come independently of the track-circuit.

My invention consists in arranging a relay so that the winding connected to the independent source produces magnetic poles on both sides of the poles produced by the wind ing connected to the track-circuit. With this arrangement, if the poles are all of equal strength, only one-third of the energy is taken from the track-circuit, 'while if the middle poles are made only half as strong as the other poles (an arrangement which is satisfactory in operation) only one-fifth of the energy is taken from the track-circuit. The symmetrical arrangement above described gives the further advantage of preventing any torque due to leakage fiuX in the core of the track-winding when the trackwinding is deenergized.

My invention will best be understood by reference to the accompanying drawings, in which Figure 1 shows diagrammatically a signal system provided with polyphase relays arranged in accordance with my invention. Fig. 2 shows a side elevation, and Fig. 3 a plan view, of a relay arranged in accordance with my invention.

In Fig. l, T represents the third rail or other supply-conductor for the driving-motors on the cars or trains. R represents the track-rails, which are sectioned so as to form blocks in the same manner as on steamroads. crepresents alternating-current-supply-conductors to which are connected transformers tfor supplying alternating current at low voltage to the rail-circuits of the blocks. Other transformers t are connected to the opposite ends of the blocks for supplying the track-relays. It will be noted that the central points on the transformer-windings in the track-circuit at adjacent ends of adjacent blocks are connected together, so as to form a path for the power-current. The blocks in this manner are connected together, so as to form a continuous return-conductor for the power-current, and since the connections between adjacent blocks are made at equipotential points the flow of alternating current is not affected. This connection whereby the same conductors are enabled to carry two different currents without interference is fully explained in Patents Nos. 645,907 and 647 ,7 41, to Bedell, issued, respectively, March 20, 1900, and April 17, 1900.

It will be noted that I have shown in Fig. 1 two coils C and only one coil C. This is to indicate that the winding connected to the line-wires c produces poles on both sides of the poles produced by the winding connected to the track-circuit. With this arrangement the greater part of the energy is taken directly from the line-wires a, so that a comparatively small amount of energy is reduced is not suflicient, any well-known phase shifting devices, such as the resistances I, inserted'in any suitable circuit, may be resorted to to supplement this effect.

In Figs. 2 and 3 I have shown one suitable construction of the track-relays. The coil C, which is supplied from the track-transformer is provided with a C-shaped magnetic core, between the poles of which is mounted the disk segment D, supported on a shaft (Z. The other phase of the relay comprises two coils C, each with a C-shaped core. These cores are arranged on opposite sides of the diskD, and the poles of each of these cores are on opposite sides of one of the poles of the core of the winding C. The disk is thus threaded by one flux produced by the trackcircuit coil C and two fluxes, one on each side of the first, produced by the coils C, which are supplied from the line. This 5rrangement produces a high torque with comparatively small amount of energy in the coil C, which is supplied from the track-circuit.

Many other arrangements of the magnetic cores may be employed. It is essential only that the winding supplied from the line shgll produce fluxes threading the disk on both sides of the flux produced by the trackwinding.

WVhat I claim as new, and desire to secure by Letters Patent of the United States, is

1. An alternating-current railway signal system comprising means for supplying alternating current to the rails of the blocks, a relay comprising a conducting member, a winding supplied with current from the track-circuit arranged to produce a flux threading said member, and a winding supplied with alternating current of the same frequency and different phase independently of the track-circuit and arranged to produce two fluxes threading said member on opposite sides of the first flux, and a signal controlled by the movement of said member.

2. In an alternating-current railway signal system comprising means for supplying altern sting current to the rails of a block, a relay comprising a conducting-disk, a winding supplied with current from the track-circuit, core therefor arranged. to nroduce a flux threading said disk, a winding supplied with alternating current of the same frequency and difl'erent phase independently of the track-circuit, and magnetic cores therefor arrxnged to produce two fluxes threading said disk on. opposite sides of the first flux, and. a signal controlled by the movement of said member.

3. An clterm;.tingcurrent railway signal system comprising singlephzse mains extending along the track, connections for supplying alternn ting current to the l'nllS ol the blocks, relays comprising a conducting member, winding supplied with current from the track-circuit arranged to produce a flux tl'ireading said member, and winding supplied with current directly from said mains and arranged to produce two fluxes bl]1()n(l ing said member on opposite sides of the first flux, the circuits or the system being so arranged. that the currents in the two re windings are displaced in ph.;se from each other by substantially ninety degrees.

In witness whercol I h ave hereui'rto set my hand this 25th day ol May, 1906.

' MAX R. HANNA.

WVitnesses:

HELEN ORFORD, E. C. HoLLrs'rEn. 

